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Seroprevalence of Neutralizing Antibodies Against Japanese Encephalitis Virus Among 6 Years Old Children With 5 Different Immunization Strategies in Zhejiang Province

Primary Purpose

Japanese Encephalitis, Vaccine Preventable Disease, Vaccine Reaction

Status
Active
Phase
Phase 4
Locations
China
Study Type
Interventional
Intervention
Japanese Encephalitis Vaccine (Vero Cell), Inactivated;
No prospective interventions
Sponsored by
Zhejiang Provincial Center for Disease Control and Prevention
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional prevention trial for Japanese Encephalitis focused on measuring Japanese Encephalitis, Seroprevalence, Immunogenicity, Immunization schedule, Safety

Eligibility Criteria

72 Months - 75 Months (Child)All SexesAccepts Healthy Volunteers

Inclusion Criteria:

  • Participants aged ≥ 72 months to < 75 months.
  • Participants have completed routine immunization schedules in time.
  • Participants are healthy native residents.
  • Parents/guardians can understand the protocol requirements, provide informed consent, accept all scheduled visits, and comply with all trial procedures.

Exclusion Criteria:

  • History of neurological diseases or related symptoms.
  • An acute illness with fever (temperature ≥ 37.1℃) or any acute onset of chronic diseases.
  • Known impairment of immunologic function, or receipt of immunosuppressive therapy or immunoglobulin in the past 3 months.
  • Known allergy to any constituent of the vaccine.
  • Have been injected with other vaccines or any clinical trial drugs in the past 4 weeks.
  • Any condition which, in the opinion of the investigator, would pose a health risk to the subject or interfere with the vaccine.

Sites / Locations

  • Liandu center for disease control and prevention
  • Kecheng center for disease control and prevention
  • Pingyang center for disease control and prevention

Arms of the Study

Arm 1

Arm 2

Arm 3

Arm 4

Arm 5

Arm Type

Experimental

Experimental

Experimental

Experimental

Experimental

Arm Label

3JEV-I (Group 1)

JEV-L+JEV-I (Group 2)

JEV-L+2JEV-I (Group 3)

2JEV-I+JEV-L (Group 4)

2JEV-L (Group 5)

Arm Description

Retrospective: 3 doses of JE vaccines. 2 doses of Inactivated JE Vaccine (JEV-I, 7-10 days apart) at 8 months of age and 1 dose of JEV-I at 2 years old. Prospective: 1 booster dose of JEV-I at 6 years old.

Retrospective: 2 doses of JE vaccines. 1 dose of JE attenuated live vaccine (JEV-L) at 8 months of age and 1 dose of JEV-I at 2 years old. Prospective: 1 booster dose of JEV-I at 6 years old.

Retrospective: 3 doses of JE vaccines. 1 dose of JEV-L at 8 months of age and 2 dose (7-10 days apart) of JEV-I at 2 years old.

Retrospective: 3 doses of JE vaccines. 2 doses of JEV-I (7-10 days apart) at 8 months of age and 1 dose of JEV-L at 2 years old.

Retrospective: 2 doses of JE vaccines. 2 doses of JEV-L respectively administered at 8 months of age and 2 years old.

Outcomes

Primary Outcome Measures

Proportions of seropositivity of neutralizing antibodies against JE at the age of 6
Defined as any positive antibody (neutralizing antibody titers ≥1:10) response in children aged 6.
Geometric Mean Titers (GMTs) or Median antibody titers for children aged 6 years
Neutralizing antibody titers by plaque-reduction neutralization tests (PRNT).

Secondary Outcome Measures

Seroconversion rates of the booster dose of JEV-I for Group 1 and Group 2
Defined as any positive antibody (neutralizing antibody titers ≥1:10) response in children who were seronegative prior to the booster dose, or at least a four-fold increase for children who had pre-existing positive antibodies.
Proportion of seropositivity of neutralizing antibodies against JE after the booster dose for Group 1 and Group 2.
Defined as any positive antibody (neutralizing antibody titers ≥1:10) response after the booster dose.
Geometric Mean Titers (GMTs) or Median antibody titers after the booster dose for Group 1 and Group 2.
Neutralizing antibody titers by PRNT.
Safety of the booster dose for Group 1 and Group 2
The occurrence of adverse events for the booster dose

Full Information

First Posted
March 23, 2021
Last Updated
November 13, 2022
Sponsor
Zhejiang Provincial Center for Disease Control and Prevention
Collaborators
Liaoning Chengda Biotechnology CO., LTD
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1. Study Identification

Unique Protocol Identification Number
NCT04817917
Brief Title
Seroprevalence of Neutralizing Antibodies Against Japanese Encephalitis Virus Among 6 Years Old Children With 5 Different Immunization Strategies in Zhejiang Province
Official Title
Seroprevalence of Neutralizing Antibodies Against Japanese Encephalitis Virus Among 6 Years Old Children With 5 Different Immunization Strategies in Zhejiang Province, China: An Open-labeled, Ambidirectional Cohort Study
Study Type
Interventional

2. Study Status

Record Verification Date
July 2022
Overall Recruitment Status
Active, not recruiting
Study Start Date
March 1, 2021 (Actual)
Primary Completion Date
September 17, 2022 (Actual)
Study Completion Date
June 30, 2023 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Sponsor
Name of the Sponsor
Zhejiang Provincial Center for Disease Control and Prevention
Collaborators
Liaoning Chengda Biotechnology CO., LTD

4. Oversight

Studies a U.S. FDA-regulated Drug Product
No
Studies a U.S. FDA-regulated Device Product
No

5. Study Description

Brief Summary
This study is to evaluate the seroprevalence of neutralizing antibodies against Japanese encephalitis (JE) virus in children aged 6 years who were previously administered with 5 different immunization strategies by JE attenuated live vaccine (JEV-L) or/and inactivated vaccine (JEV-I). The secondary objective is to evaluate the immunogenicity of the booster dose of JEV-I at 6 years old for those previously immunized with 3 doses of JEV-I or those sequential administered with 1 dose of JEV-L and another dose of JEV-I.
Detailed Description
Based on the retrospective registry in Zhejiang Provincial Immunization Information System, healthy children aged 6 years from 5 cohorts were included according to their previous immunization schedules on JE: 3 doses of JEV-I (Group 1), JEV-L+ JEV-I (Group 2), JEV-L+ JEV-I + JEV-I (Group 3), JEV-I + JEV-I+ JEV-L (Group 4), and 2 doses of JEV-L (Group 5). According to immunization programs in China, a booster dose of JEV-I is needed at the age of 6 for Group 1 and Group 2. A pre-vaccination blood sample (2.5ml) will be collected to evaluate the proportions of seropositivity before the booster dose of JEV-I. A second blood sample will be collected 28-35 days after the booster dose. Immunogenicity of the booster dose will be assessed by seroconversion rates, proportions of seropositivity and GMTs for these two groups. In addition, safety will be assessed with the occurrence of adverse events reported in these two groups. For the rest three groups who have completed the immunization schedules on JE, only one blood sample will be taken at the age of 6 to evaluate the proportions of seropositivity and GMTs after 4 years post the complete immunization schedules. Plague reduction neutralization test (PRNT) against both vaccine strains (SA-14-14-2 strain for JEV-L and Beijing P3 strain for JEV-I) will be used to test neutralizing antibody titers, so as to avoid potential bias in favor of either vaccine. PRNT50 titers (the reciprocal of the serum dilution that reduced the virus plaque count by 50% compared with the virus-only controls) ≥ 1:10 are deemed as positive.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Japanese Encephalitis, Vaccine Preventable Disease, Vaccine Reaction
Keywords
Japanese Encephalitis, Seroprevalence, Immunogenicity, Immunization schedule, Safety

7. Study Design

Primary Purpose
Prevention
Study Phase
Phase 4
Interventional Study Model
Parallel Assignment
Masking
None (Open Label)
Allocation
Non-Randomized
Enrollment
712 (Actual)

8. Arms, Groups, and Interventions

Arm Title
3JEV-I (Group 1)
Arm Type
Experimental
Arm Description
Retrospective: 3 doses of JE vaccines. 2 doses of Inactivated JE Vaccine (JEV-I, 7-10 days apart) at 8 months of age and 1 dose of JEV-I at 2 years old. Prospective: 1 booster dose of JEV-I at 6 years old.
Arm Title
JEV-L+JEV-I (Group 2)
Arm Type
Experimental
Arm Description
Retrospective: 2 doses of JE vaccines. 1 dose of JE attenuated live vaccine (JEV-L) at 8 months of age and 1 dose of JEV-I at 2 years old. Prospective: 1 booster dose of JEV-I at 6 years old.
Arm Title
JEV-L+2JEV-I (Group 3)
Arm Type
Experimental
Arm Description
Retrospective: 3 doses of JE vaccines. 1 dose of JEV-L at 8 months of age and 2 dose (7-10 days apart) of JEV-I at 2 years old.
Arm Title
2JEV-I+JEV-L (Group 4)
Arm Type
Experimental
Arm Description
Retrospective: 3 doses of JE vaccines. 2 doses of JEV-I (7-10 days apart) at 8 months of age and 1 dose of JEV-L at 2 years old.
Arm Title
2JEV-L (Group 5)
Arm Type
Experimental
Arm Description
Retrospective: 2 doses of JE vaccines. 2 doses of JEV-L respectively administered at 8 months of age and 2 years old.
Intervention Type
Biological
Intervention Name(s)
Japanese Encephalitis Vaccine (Vero Cell), Inactivated;
Intervention Description
The investigators recruit 6 years old children who have been vaccinated by 2-3 doses of JE vaccines with different immunization strategies. For participants from Group 1 and Group 2 who haven't completed the JE immunization schedules, a booster dose of JEV-I will be administered at 6 years old.
Intervention Type
Other
Intervention Name(s)
No prospective interventions
Intervention Description
The investigators recruit 6 years old children who have been vaccinated by 2-3 doses of JE vaccines with different immunization strategies. Participants from Group 3-5 have completed the JE immunization schedules with JEV-I or/and JEV-L. No prospective intervention will be given.
Primary Outcome Measure Information:
Title
Proportions of seropositivity of neutralizing antibodies against JE at the age of 6
Description
Defined as any positive antibody (neutralizing antibody titers ≥1:10) response in children aged 6.
Time Frame
At the age of 6. Test immediately after enrollment by a dose of blood sample.
Title
Geometric Mean Titers (GMTs) or Median antibody titers for children aged 6 years
Description
Neutralizing antibody titers by plaque-reduction neutralization tests (PRNT).
Time Frame
At the age of 6. Test immediately after enrollment by a dose of blood sample.
Secondary Outcome Measure Information:
Title
Seroconversion rates of the booster dose of JEV-I for Group 1 and Group 2
Description
Defined as any positive antibody (neutralizing antibody titers ≥1:10) response in children who were seronegative prior to the booster dose, or at least a four-fold increase for children who had pre-existing positive antibodies.
Time Frame
before and 28-35 days after the booster dose.
Title
Proportion of seropositivity of neutralizing antibodies against JE after the booster dose for Group 1 and Group 2.
Description
Defined as any positive antibody (neutralizing antibody titers ≥1:10) response after the booster dose.
Time Frame
28-35 days after the booster dose.
Title
Geometric Mean Titers (GMTs) or Median antibody titers after the booster dose for Group 1 and Group 2.
Description
Neutralizing antibody titers by PRNT.
Time Frame
28-35 days after the booster dose.
Title
Safety of the booster dose for Group 1 and Group 2
Description
The occurrence of adverse events for the booster dose
Time Frame
From inoculation to 30 days after the inoculation.

10. Eligibility

Sex
All
Minimum Age & Unit of Time
72 Months
Maximum Age & Unit of Time
75 Months
Accepts Healthy Volunteers
Accepts Healthy Volunteers
Eligibility Criteria
Inclusion Criteria: Participants aged ≥ 72 months to < 75 months. Participants have completed routine immunization schedules in time. Participants are healthy native residents. Parents/guardians can understand the protocol requirements, provide informed consent, accept all scheduled visits, and comply with all trial procedures. Exclusion Criteria: History of neurological diseases or related symptoms. An acute illness with fever (temperature ≥ 37.1℃) or any acute onset of chronic diseases. Known impairment of immunologic function, or receipt of immunosuppressive therapy or immunoglobulin in the past 3 months. Known allergy to any constituent of the vaccine. Have been injected with other vaccines or any clinical trial drugs in the past 4 weeks. Any condition which, in the opinion of the investigator, would pose a health risk to the subject or interfere with the vaccine.
Facility Information:
Facility Name
Liandu center for disease control and prevention
City
Lishui
State/Province
Zhejiang
ZIP/Postal Code
323000
Country
China
Facility Name
Kecheng center for disease control and prevention
City
Quzhou
State/Province
Zhejiang
ZIP/Postal Code
324000
Country
China
Facility Name
Pingyang center for disease control and prevention
City
Wenzhou
State/Province
Zhejiang
ZIP/Postal Code
325400
Country
China

12. IPD Sharing Statement

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Seroprevalence of Neutralizing Antibodies Against Japanese Encephalitis Virus Among 6 Years Old Children With 5 Different Immunization Strategies in Zhejiang Province

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